Many of my wishlist have been mentioned already but I would be dreaming of…
Dark Sun dual book set - full length campaign book & Campaign Setting
Birthright dual book set - full length campaign book & Campaign Setting
Eberron full length campaign book.
Forgotten realms full campaign book ideally set in the Dalelands and involving Myth Drannor
A reboot of Night Below
A Ravenloft full length campaign book involving several domains
Either an advanced DMG or a series of articles to adjust 5e to be gritty/grimdark/low magic etc. We’re talking action point system, lingering injuries, critical hit tables, different healing. Low magic alternatives for classes like bard and ranger etc
A brand new campaign setting for D&D that resembled Dark Ages Europe. With an accompanying full length adventure. 13th warrior vibes.
An anthology of adventures designed to take place in an urban metropolis. That involve the different organisations and locations PCs might interact with, a church of knowledge, a wizards guild, a thieves guild, a tavern, a guard house etc.
Any of those would make me a very happy bunny.